Self-Interacting Dark Matter and flavor anomalies in an atlas of leptophilic models

TL;DR

This paper explores leptophilic models with non-universal charges that can simultaneously explain the muon g-2 anomaly and provide a viable self-interacting dark matter candidate, aligning with astrophysical observations.

Contribution

It introduces a unified leptophilic model with a light vector boson that addresses both the muon g-2 anomaly and small-scale structure issues in dark matter.

Findings

A vector boson of ~10 MeV mediates relevant interactions.

Dark matter candidates with 10-100 GeV mass fit the model.

Strong dark sector coupling explains astrophysical small-scale problems.

Abstract

We consider an atlas of leptophilic models with non-universal charges that combine the quantum numbers \((L_e - L_{\mu})\) and \((L_{\mu} - L_{\tau})\) in various realizations. We explore diverse manifestations of the atlas to understand their impact on explaining the muon \((g-2)_{\mu}\) anomaly, as well as the origin of self-interacting dark matter, which serves as a feasible explanation for the small-scale challenges of cold dark matter. We found that a single vector gauge boson with mass range of $\sim 10~\mathrm{MeV}$ and non-universal couplings as indicated successfully mediates interactions in the fermion and dark matter sectors in such a way that $(g-2)_{\mu}$ additional contribution agrees with experimental constraints and the self-interacting dark matter fluid behaves as suggested by observations at different astrophysical length scales. Furthermore, the model requires a dark matter candidate within $10-100~ \mathrm{GeV}$ order mass and a strong dark coupling ($g_{\chi} \sim 0.3$, much stronger than the lepton's couplings $g'_l \lesssim 10^{-4}$) to be a successful scenario to unravel astrophysical small scale problems.